<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>去除字符串左右空格</title>
	</head>
	<body>
		<script type="text/javascript">
			function trim(s){  
				return trimRight(konggeLeft(s));  
			}  
			document.write(trim('    sdfdfssdfdfszz   '));
//去掉左边的空白  
			function konggeLeft(s){  
				if(s == null) {  
					return "";  
				}  
				var whitespace = new String(" \t\n\r");  
				var str = new String(s);  
				if (whitespace.indexOf(str.charAt(0)) != -1) {  
					var j=0, i = str.length;  
					while (j < i && whitespace.indexOf(str.charAt(j)) != -1){  
						j++;  
					}  
					str = str.substring(j, i);  
				}  
				return str;  
			}  
//去掉右边的空白    
			function trimRight(s){  
				if(s == null) return "";  
				var whitespace = new String(" \t\n\r");  
				var str = new String(s);  
				if (whitespace.indexOf(str.charAt(str.length-1)) != -1){  
					var i = str.length - 1;  
					while (i >= 0 && whitespace.indexOf(str.charAt(i)) != -1){  
						i--;  
					}  
					str = str.substring(0, i+1);  
				}  
				return str;  
			}
		</script>
	</body>
</html>
